In her new book, "The Moment of Lift: How Empowering Women Changes the World," Gates explores ways in which we can uplift women in order to address the inequalities they face at work and at home. She also writes about her journey to negotiating equality in her own life, including in her marriage to billionaire entrepreneur and philanthropist Bill Gates.

She tells CNBC Make It's Jenna Goudreau that she always knew she wanted an equal partnership that wasn't constrained by the traditional gender roles and responsibilities often placed on women. "The good news," she says, "was [Bill] had a mom who both was at home and working. She did many things in the community and was on several boards."

Bill and Melinda Gates arrive at the Elysee Palace before receiving the award of Commander of the Legion of Honor by French President Francois Hollande.

Frederic Stevens | Getty Images

"He had a grandmother who went to college when most women didn't," she says. Seeing these ambitious women in his own life, Gates explains, led Bill to seek an equal partnership in his marriage.

But she says there were still times when "we just didn't realize we had fallen back into our own sort of biases about who does what." And when this happened, she says, "I had to name at home what I needed."

For example, Gates shares that when the couple was preparing for their first daughter to start kindergarten, she and Bill had agreed on the perfect school, which was about 45 minutes, round-trip, from their home. But then she started thinking about the time she would spend sitting in traffic and how much that would add up over the years, and suggested to Bill that they wait until their daughter was in the third grade before enrolling her in that school. Yet he was adamant that she start there immediately.

So Bill said, "'What could I do?'" says Gates. "'What could I do to make it easier?' And I said, 'Well, you could drive.'"

From then on, she says, Bill drove their daughter to school two days a week, bringing his round-trip commute from their home, to the school, and back to Microsoft, to an hour. "What I didn't realize at the time," Gates says, "was by asking what I needed at home — which is this category we all call 'unpaid work,' and naming what the burdens of that were on me — I allowed him to step in."

As a result, she says, they became unintentional role models for other parents at the school.

"Three weeks in, I started to notice more dads were driving and showing up with their kids," she says. "And a mom said to me, 'Do you see what's going on here?' And I was like, 'Well, I don't know. More dads are dropping off.'

"And she says, 'Yeah, we went home with our hands on hips and said, 'If Bill Gates can drive his kids to school, then by gosh, you can too!'"

Gates says the experience showed her the value of questioning the expectations society automatically applies to women. When those expectations are reconsidered, she says, it's possible to "role model something new."